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From: Niklas Holsti <niklas.holsti@tidorum.invalid>
Newsgroups: comp.lang.ada
Subject: Re: Valid attribute and input operations
Date: Tue, 26 Sep 2023 10:22:14 +0300
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On 2023-09-26 9:13, Randy Brukardt wrote:

> ... for Janus/Ada, enumeration types with specified representations
> operate internally on the position numbers


Hm, that's interesting. Is that also the representation for record 
components of such an enumerated type?

For example, if I have:

    type Command is (Off, On) with Size => 4;
    for Command use (Off => 2, On => 5);
    type Two_Commands is record
       C1, C2: Command;
    end record
    with Pack, Size => 8;

    TwoC : Two_Commands := (C1 => On, C2 => Off);

will the record components (in memory) have the values C1 = 1 and C2 = 0 
(position numbers) or C1 = 5, C2 = 2 (specified representation)?

If they are represented by position numbers in the record, many if not 
most of my embedded Ada programs would fail if compiled with Janus/Ada, 
because the record values stored in I/O control registers or accessed 
via DMA would be wrong.

Damn, I thought those programs were not so compiler-dependent :-(